<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>

  <body>
    <div id="a">小滴课堂</div>
    <script>
      document.write('hello world');
      var text = document.getElementById('a');
      text.onclick = function () {
        alert('你点击了小滴课堂');
      };
      
    </script>
  </body>
</html>
